Change search
CiteExportLink to record
Permanent link

Direct link
Cite
Citation style
  • apa
  • harvard1
  • ieee
  • modern-language-association-8th-edition
  • vancouver
  • Other style
More styles
Language
  • de-DE
  • en-GB
  • en-US
  • fi-FI
  • nn-NO
  • nn-NB
  • sv-SE
  • Other locale
More languages
Output format
  • html
  • text
  • asciidoc
  • rtf
Stereoselective synthesis of semiochemicals related to pine sawflies
KTH, Superseded Departments, Chemistry.
1999 (English)Doctoral thesis, comprehensive summary (Other scientific)
Abstract [en]

This thesis describes the stereochemistry and charactericsof (–)-1,6-germacradien-5-ol, isolated from the larvaldefence substance of the pine sawflyNeodiprion sertiferand from the needles of Scots pine,Pinus sylvestris. The conformational behaviour of thissesquiterpene alcohol was investigated by molecular mechanicsstudies (MM2) and NMR. The absolute configuration at the twostereogenic centres was established as (5S,8S), after NOE measurements and chemical transformationinto (–)-α-cadinol and 1-endo-bourbonanol. Our studies towards a stereoselectivetotal synthesis of (–)-1,6-germacradien-5-ol using ringclosing metathesis (RCM) is also reported. However, allattempts to prepare this germacrene alcohol and other1,6-cyclodecadien systems using RCM failed.

Pseudomonas cepacialipase (PCL) catalysed acylation ofprimary 2-methylalcohols with vinyl acetate is anenantioselective reaction. The enantioselectivity of PCLtowards a series of primary 2-methylalcohols were studied. Highenantiomeric ratios,E>100, were observed for2-methyl-3-aryl-1-propanols, where aryl is 2-thiophene,3-thiophene, 2-furan and phenyl. In contrast the selectivitywas rather low for other 3-substituted primary2-methylpropanols such as 3-alkyl and 3-cycloalkyl, E ≈10 - 20. When moving the thiophene ring closer or further awayfrom the stereogenic centre a dramatic decrease in E wasobserved. 2-Isopropyl-5-methyl-5-hexen-1-ol, a possiblebuilding block for the total synthesis of1,6-germacradien-5-ol, was also successfully resolved with PCL,E= 14.

Keywords:defence substance, 1,6-germacradien-5-ol,Neodiprion sertifer,Pinus sylvestris, molecular mechanics, configuration,metathesis, RCM, stereoselective, kinetic resolution,transesterification, lipase,Pseudomonas, PCL, 2-methylalcohol, 2-isopropylalcoholenantioselective.

Place, publisher, year, edition, pages
Stockholm: Kemi , 1999. , vi, 54 p.
Series
Trita-IOK, ISSN 1100-7974 ; 56
Identifiers
URN: urn:nbn:se:kth:diva-2852ISBN: 99-3016099-X OAI: oai:DiVA.org:kth-2852DiVA: diva2:8578
Public defence
1999-10-08
Note
NR 20140805Available from: 2000-01-01 Created: 2000-01-01Bibliographically approved

Open Access in DiVA

fulltext(953 kB)1447 downloads
File information
File name FULLTEXT01.pdfFile size 953 kBChecksum MD5
f3f3c08fee3bb9802f0c40c8f99d29225f96f84cb99734acfa139107f98d206cddf6a4f2
Type fulltextMimetype application/pdf

By organisation
Chemistry

Search outside of DiVA

GoogleGoogle Scholar
Total: 1450 downloads
The number of downloads is the sum of all downloads of full texts. It may include eg previous versions that are now no longer available

isbn
urn-nbn

Altmetric score

isbn
urn-nbn
Total: 360 hits
CiteExportLink to record
Permanent link

Direct link
Cite
Citation style
  • apa
  • harvard1
  • ieee
  • modern-language-association-8th-edition
  • vancouver
  • Other style
More styles
Language
  • de-DE
  • en-GB
  • en-US
  • fi-FI
  • nn-NO
  • nn-NB
  • sv-SE
  • Other locale
More languages
Output format
  • html
  • text
  • asciidoc
  • rtf